AZD7762 is a novel ATP competitive inhibitor of checkpoint kinases. Chk family checkpoint kinases include Chk1 and Chk2. They are activated in response to DNA damage and phosphorylate CDC25A, CDC25C protein phosphatases, which delay cell cycle progression. Therefore, Chk activation initiates cell cycle checkpoint, causes cell cycle arrest, and allows DNA repair.
AZD7762 is a potent selective inhibitor of Chk1. It binds to the ATP binding pocket and compete ATP binding in a reversible manner. AZD7762 inhibits Chk1 phosphorylation of CDC25C peptide with an IC50 of 5 nM. The Ki is 3.6 nM. It is equally potent against Chk2 but less potent against CAM, Yes, Fyn, Lyn, Hck and Lck. [1]
AZD7762 prevents cell cycle arrest and DNA repair in DNA damaged tumor cells, causing tumor cell apoptosis. Hence, it potentiates the antitumor activity of DNA damaging agents and can be used as a chemosensitizing agent. [2]
Half life of AZD7762 is 1-2 hours in mice [3]
References:
[1]Zabludoff SD, et al. AZD7762, a novel checkpoint kinase inhibitor, drives checkpoint abrogation and potentiates DNA-targeted therapies. Mol Cancer Ther, 2008, 7(9): 2955-2966.
[2]Landau HJ, et al. The checkpoint kinase inhibitor AZD7762 potentiates chemotherapy-induced apoptosis of p53-mutated multiple myeloma cells. Mol Cancer Ther. 2012, 11(8): 1781-1788
[3]Goteti K, et al. Preclinical pharmacokinetic/pharmacodynamic models to predict synergistic effects of co-administered anti-cancer agents. Cancer Chemother Pharmacol. 2010, 66(2): 245-254.